Pumping systems are important for chemical analysis, drug delivery, and analyte sampling. However, traditional pumping systems can be inefficient due to a loss of power incurred by movement of a mechanical piston. For example, as shown in FIGS. 2B and 3B, when a piston 203 is used between two diaphragms 254, 252, the piston 203 typically pushes and pulls on part of the diaphragms 254, 252, thus expanding and contracting in and out of a pumping chamber 122. This contraction and expansion pumps the fluid. Inefficiencies occur, however, because the mechanical piston 203 can only actuate the areas of the diaphragms 252, 254 with which it has contact. Other parts 255 of the diaphragms 252, 254 that are not acted upon on by the piston 203 are left to flex freely as the piston 203 is moving. As a result, fluid in contact with or near these areas of the diaphragm is unable to move, therefore robbing efficiency from the pump.
Some diaphragm designs try to compensate for such inefficiencies by using a stiffer material to avoid having the diaphragm freely flexing. This approach, however, makes the diaphragm more difficult to actuate and tends to still lower efficiency. Other conventional diaphragm designs, such as a rolling diaphragm, are easy to actuate but have larger dead volumes.
Traditional systems can also be disadvantageous because they cannot precisely deliver small amounts of delivery fluid, partly because a mechanical piston cannot be accurately stopped mid-stroke.
Moreover, traditional pumping systems can be disadvantageous because they are often large, cumbersome, and expensive. Part of the expense and size results from the fact that the current pumping systems require the engine, pump, and controls to be integrated together.
Accordingly, a pumping system is needed that is highly efficient, precise, and/or modular.